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Many Gaps (many + gap)
Selected AbstractsChallenging Wallacean and Linnean shortfalls: knowledge gradients and conservation planning in a biodiversity hotspotDIVERSITY AND DISTRIBUTIONS, Issue 5 2006Luis Mauricio Bini ABSTRACT Knowledge about biodiversity remains inadequate because most species living on Earth were still not formally described (the Linnean shortfall) and because geographical distributions of most species are poorly understood and usually contain many gaps (the Wallacean shortfall). In this paper, we developed models to infer the size and placement of geographical ranges of hypothetical non-described species, based on the range size frequency distribution of anurans recently described in the Cerrado Biome, on the level of knowledge (number of inventories) and on surrogates for habitat suitability. The rationale for these models is as follow: (1) the range size frequency distribution of these species should be similar to the range-restricted species, which have been most recently described in the Cerrado Biome; (2) the probability of new discoveries will increase in areas with low biodiversity knowledge, mainly in suitable areas, and (3) assuming range continuity, new species should occupy adjacent cells only if the level of knowledge is low enough to allow the existence of undiscovered species. We ran a model based on the number of inventories only, and two models combining effects of number of inventories and two different estimates of habitat suitability, for a total of 100 replicates each. Finally, we performed a complementary analysis using simulated annealing to solve the set-covering problem for each simulation (i.e. finding the smallest number of cells so that all species are represented at least once), using extents of occurrence of 160 species (131 real anuran species plus 29 new simulated species). The revised reserve system that included information about unknown or poorly sampled taxa significantly shifted northwards, when compared to a system based on currently known species. This main result can be explained by the paucity of biodiversity data in this part of the biome, associated with its relatively high habitat suitability. As a precautionary measure, weighted by the inferred distribution data, the prioritization of a system of reserves in the north part of the biome appears to be defensible. [source] Consumers' perceptions and awareness of food safety practices in Barbados and Trinidad, West Indies , a pilot studyINTERNATIONAL JOURNAL OF CONSUMER STUDIES, Issue 4 2008Ranate Odwin Abstract The objectives of this pilot study were to determine perception and awareness of food safety practices of consumers in Trinidad and Barbados. A structured questionnaire was self-administered to 148 respondents. Data were analysed by descriptive and chi-square analysis. Most (92%) consumers rated having safe food practices as ,very important'. Only 25.7% heard of the acronym ,HACCP' (Hazard Analysis and Critical Control Point), associated the HACCP approach to safe food preparation (25.7%) and reported it recommendatory in homes (19.6%). More than one-third (45.6%) felt that up to 20% of food poisoning was associated to the home. Over the last 12 months, 18.2% of consumers and/or family members had experienced food-borne illness, but no one associated it to the home. More (P < 0.01) consumers in Trinidad than in Barbados were aware of the HACCP, experienced food-borne illness and allowed pets in the kitchen. This study identified many gaps in proper food safety practices in the homes. [source] Host,parasite relations of an angiospermous root parasite (Thonningia sanguinea Vahl) in logged and unlogged sites of Budongo forest reserve, western UgandaAFRICAN JOURNAL OF ECOLOGY, Issue 3 2009Concy Acen Olanya Abstract Host,parasite relationships of an angiospermous root parasite (Thonningia sanguinea) were investigated in logged and unlogged sites of Budongo Forest Reserve. Host trees were identified and their diameters measured in 20 × 20 m plots established randomly in sites where the parasites were presumed to occur. The distance of the point of attachment of the parasite from the base of the host stem was determined and overstorey density measured at the centre of each plot. There were more parasites in the logged than in the unlogged sites (878 and 425 individual parasites ha,1 respectively). The parasite was not host specific but Alchornea laxiflora (Benth) Pax and K.Hoffm, Celtis mildbraedii Engl and Lasiodiscus mildbraedii Engl had relatively more parasites than other species. The parasite could be found within a radius of 2 m from the base of the host stem. The diameter of hosts ranged from 1 to 95 cm. There was a positive correlation between overstorey density and occurrence of T. sanguinea. Conservation of T. sanguinea, therefore, requires maintenance of intact forests with closed canopies rather than logged sites with many gaps and hence low overstorey density. Résumé On a étudié les relations hôte-parasite d'un angiosperme parasite des racines (Thonningia sanguinea) sur des sites exploités ou non de la Réserve forestière de Budongo. On a identifié les arbres hôtes et on a mesuré leur diamètre dans des parcelles de 20 × 20 m établies au hasard dans des sites où le parasite était supposé se trouver. La distance entre le point d'ancrage du parasite et la base du tronc de l'hôte fut déterminée, et la densité de la végétation aérienne fut mesurée au centre de chaque parcelle. Il y avait plus de parasites dans les parcelles exploitées que dans les parcelles nonexploitées (878 et 425 parasites par ha, respectivement). Le parasite n'était pas spécifique de l'hôte, mais Alchornea laxiflora (Benth) Pax et K.Hoffm, Celtis mildbraedii Engl et Lasiodiscus mildbraedii Engl avaient relativement plus de parasites que d'autres espèces. Le parasite peut se trouver dans un rayon de deux mètres de la base du tronc de l'hôte. Le diamètre du tronc de l'hôte variait de 1 à 95 cm. Il y avait une corrélation positive entre la densité de la végétation aérienne et l'occurrence de T. sanguinea. Donc, la conservation de T. sanguinea requiert la préservation de forêts intactes avec des canopées fermées plutôt que des sites exploités avec des nombreuses clairières et donc, une faible densité de couverture végétale. [source] The black,white "achievement gap" as a perennial challenge of urban science education: A sociocultural and historical overview with implications for research and practice,JOURNAL OF RESEARCH IN SCIENCE TEACHING, Issue 10 2001Obed Norman A perennial challenge for urban education in the United States is finding effective ways to address the academic achievement gap between African American and White students. There is widespread and justified concern about the persistence of this achievement gap. In fact, historical evidence suggests that this achievement gap has existed at various times for groups other than African Americans. What conditions prevailed when this achievement gap existed for these other groups? Conversely, under what conditions did the gap diminish and eventually disappear for these groups? This article explores how sociocultural factors involved in the manifestation and eventual disappearance of the gap for these groups may shed some light on how to address the achievement gap for African American students in urban science classrooms. Our conclusion is that the sociocultural position of groups is crucial to understanding and interpreting the scholastic performance of students from various backgrounds. We argue for a research framework and the exploration of research questions incorporating insights from Ogbu's cultural, ecological theory, as well as goal theory, and identity theory. We present these as theories that essentially focus on student responses to societal disparities. Our ultimate goal is to define the problem more clearly and contribute to the development of research-based classroom practices that will be effective in reducing and eventually eliminating the achievement gap. We identify the many gaps in society and the schools that need to be addressed in order to find effective solutions to the problem of the achievement gap. Finally, we propose that by understanding the genesis of the gap and developing strategies to harness the students' responses to societal disparities, learning can be maximized and the achievement gap can be significantly reduced, if not eliminated entirely, in urban science classrooms. © 2001 John Wiley & Sons, Inc. J Res Sci Teach 38: 1101,1114, 2001 [source] Addressing the epidemic of chronic kidney disease in AustraliaNEPHROLOGY, Issue 2004Timothy MATHEW SUMMARY: The Australia Diabetes, Obesity and Lifestyle Study (AUSDIAB) study provided, for the first time in Australia, a snapshot of the prevalence of kidney damage, reduced kidney function, hypertension and diabetes in the adult population. With this information, and the Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) registry, that has recorded kidney failure statistics for many years, the extent of the chronic kidney disease burden in Australia is being better defined. This burden is even more pronounced in the Indigenous population where the incidence of kidney disease and kidney failure is increased several-fold. Diabetes is the second most common cause of kidney failure among Australians. The number of patients with diabetes accepted to dialysis has doubled in the last 7 years, the mean body weight of patients commencing dialysis has increased 7 kg in the past decade and the mean age at acceptance to dialysis is rising in a linear fashion (presently 60 years). These facts, together with a static transplant rate, all point to the prevalence of dialysis likely staying at or increasing beyond the present yearly growth rate of 6,7%. The evidence shows that a large proportion of chronic kidney disease patients are dying of cardiovascular risk factors before they reach dialysis or transplantation. There are many gaps in delivering appropriate preventative treatment to these patients. A relatively small reduction in the rise in dialysis numbers that might flow from an effective prevention of progression program, could make a significant impact on the spiralling numbers and associated cost of kidney failure treatment in Australia. We now need to develop and implement a national kidney disease strategy designed to address the whole continuum of chronic kidney disease from its earliest stage right through to dialysis and transplantation. [source] An exploratory study of gambling motivations and their impact on the purchase frequencies of various gambling productsPSYCHOLOGY & MARKETING, Issue 9 2007Desmond Lam The global gambling industry is huge and gambling has become a leading leisure activity in many countries. Although research on gambling is extensive, many gaps remain. The objective of this exploratory study was to examine how motivations for regular gambling varied by the forms of game played. Using data collected by the U.S. National Gambling Impact Study Commission, the study found that regular gamblers were motivated to gamble to win and to fulfill their sense of excitement/challenge for some gambling products like lottery, racetrack betting, and casinos. For others, such as bingo and card room games, they were motivated to gamble more for social reasons. The findings have important implications to marketers and public policy makers. © 2007 Wiley Periodicals, Inc. [source] Controllable Synthesis of Nickel Hydroxide and Porous Nickel Oxide Nanostructures with Different MorphologiesCHEMISTRY - A EUROPEAN JOURNAL, Issue 16 2008Lihong Dong Dr. Abstract ,-Ni(OH)2 nanobelts, nanowires, short nanowires, and ,-Ni(OH)2 nanoplates have been successfully prepared in high yields and purities by a convenient hydrothermal method under mild conditions from very simple systems composed only of NaOH, NiSO4, and water. It has been found that the ratio of NaOH to NiSO4 not only affects the morphology of the Ni(OH)2 nanostructures, but also determines whether the product is of the ,- or ,-crystal phase. A notable finding is that porous NiO nanobelts were produced after exposure of the Ni(OH)2 products to an electron beam for several minutes during transmission electron microscopy (TEM) observations. Another unusual feature is that rectangular nanoplates with many gaps were obtained. Furthermore, porous NiO nanobelts, nanowires, and nanoplates could also be obtained by annealing the as-prepared Ni(OH)2 products. A sequence of dissolution, recrystallization, and oriented attachment-assisted self-assembly of nanowires into nanobelts is proposed as a plausible mechanistic interpretation for the formation of the observed structures. The method presented here possesses several advantages, including high yields, high purities, low cost, and environmental benignity. It might feasibly be scaled-up for industrial mass production. [source] Child Reactions to Terrorism: Cautions and Next Steps for ResearchCLINICAL PSYCHOLOGY: SCIENCE AND PRACTICE, Issue 3 2007Alan E. Kazdin Comer and Kendall (2007) have provided an excellent review of what is known about the effects of terrorism on children. They have identified correlates, outcomes, and the many gaps in our current knowledge. The present comments focus on two main issues. First, there are many correlates and risk factors that predict deleterious outcomes following exposure to terrorist acts. Our field occasionally moves quickly to intervention work by altering malleable risk factors as if they played a causal role in the outcome or its amelioration. More work is needed to analyze these correlates and the precise role they play, if any, in the outcome. Second, in a relatively new area of research there are very many gaps in our knowledge. I discuss the need to prioritize and limit the focus of our studies. Priorities highlighted include evaluating the similarities among natural and human-made disasters and evaluating mechanisms of action among correlates that might bear an important role in child outcomes. Apart from the consequences of terrorist acts on children and families, our field must turn to the broader issue. What can our science do alone and in conjunction with other fields to understand and combat the precursors and origins of terrorism? Theory will be wonderful but we will need to have this grounded or tested to ensure we move beyond reasonable ideas or a lavish buffet of untestable interpretations. [source] | |||||||||||||